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H Y D R ds TAT 1 G 8.

III. From the Gravity of Fluids arijestheir Prejsure , which is always proportionalthereto ; and since We may suppose all theParticles of a Fluid to have equal Bulkand Weight, the Gravity of the Fluid, andconsequently its Pressure, will be alwaysproportional to the Altitude or Depth thereof

Whence

alike in all Circumstances, they will be all equally af-fected by Attraction, and therefore have among them-<selves an equal Tendency towards the Earth’s Centre,Whence, since they gravitate equally, if they areequally obstructed in their Descent (as by the Bottomsof Vessels, (Ac. ) they will all retain the fame Positionamong themselves, as if they were affected by no Kindof Power at all; and thus they are said to be relativelyat rejl , or in a State of Quietus among themselves.

3. Since no one Particle of the fame Fluid has 3greater Share of the attracting Power than another, noone will tend to descend before another; and thereforeamong the Particles of the fame Fluid, there is no suchThing as we call Relative or Ref.dual Gravity, which isnothing but the Excess of Gravity , by which one Bodytends downwards more than another , as will be more fullyexplained hereafter (See Annotat. LVIII).

4. Now because Philosophers found that a Bucketof Water in Water weighed nothing (that is, that therewas no Relative Gravity in Water) they very strangelyinferred there was no Absolute Gravity of any Part orParticle of Water, whilst it remained in Water, butonly became heavy when taken out, or separated fromthe rest. But their Mistake is easily evinced by thefollowing Experiment; let a Bottle or Vial with Shotin it to make it sink in Water (when close corked) behung at the End of a nice Balance, and then immersedinto a Jar of Water; while thus hanging in Water, letit be counterpoised very exactly by Weights put intothe Scale at the other End, Then pulling out the Cork

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